1. Field of the Invention
The present invention relates to a pipe coupling for use in a pipe arrangement of a construction machine, a machine tool and the like, and particularly to a pipe coupling which is suitable for use in connecting and removing a pipe body in a small space where it is difficult to use a tool.
2. Description of the Related Art
For use with a pipe body which is made of relatively flexible synthetic resin or rubber, there has been proposed a pipe coupling which makes it possible to connect and remove a pipe body in a relatively simple manner.
However, when used with a relatively hard pipe body such as a polyvinyl chloride-coated hose, which is also made of synthetic resin as described above, or a metal pipe or the like, a pipe coupling which can be freely connected to and removed from such a hard pipe, has not been put to practical use.
FIG. 22 shows one example of this type of pipe coupling, which allows coupling by causing a bite piece 32 to bite a pipe body 40.
A cap nut 33 threadedly engaged with a female member 31 causes the bite piece 32 to be pressed against and to bite a surface of the pipe body 40. Thus, even if the cap nut 33 is loosened, the bite piece 32 is not easily separated from the pipe body 40, making it nearly impossible to remove the pipe body 40 from the pipe coupling. Further, if the pipe body 40 is removed from the pipe coupling, the surface of the pipe body 40 is damaged. For this reason, when the damaged pipe body 40 is re-used, there is a possibility that the fluid flowing through the pipe body 40 may leak out via the damaged portion thereof.
Therefore, a pipe coupling which is suitable for use with a metal pipe or the like and which can be freely connected to and removed from the metal pipe or the like, is not in practical use.